PEC 013
Page
55
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71
12/20/13
Gear Down Protection (GDP)
The gear down protection module encourages the driver to shift into top gear when
operating the vehicle at the target operating speed. This is done by restricting the
road speed in gears below top gear. When enabled, GDP restricts operation of the
vehicle at the target operating speed when not in top gear. This effectively prevents
engine operation at excessive RPMs and, as a result, helps to improve fuel
economy.
GDP is a “hard” limit. The engine RPM, and therefore vehicle speed, will
be limited to a specified value in the specified gears. Along with limiting engine RPM
and vehicle speed, this function also provides a visual notification to the operator to
shift via the driver display.
The gear down protection module offers a single programmable engine speed
limit. Selection of the GDP module will automatically set the engine speed limit at
one or two gears below top gear depending upon the combination of: transmission,
rear axle ratio, and tire family. Changes to the factory settings can be made post-
delivery via a PRS file from the PACCAR Engines Support Center.
Orderable Feature & Options
Feature
Sales
Code
Description
SCM: Progressive Shift
2092084
Encourages upshift at lower RPMs
SCM: Gear Down Protection
2092085
Encourages use of top gear
ON/OFF Requirements
Progressive Shift
ON
OFF
2092084 (Progressive Shift ON)
No Sales Code (Progressive Shift OFF)
GDP
ON
OFF
2092085 (Gear Down Protection ON)
No Sales Code (Gear Down Protection
OFF)
